CN105704919B - A kind of production method of edge PTH hole and PCB on PCB - Google Patents
A kind of production method of edge PTH hole and PCB on PCB Download PDFInfo
- Publication number
- CN105704919B CN105704919B CN201610109174.0A CN201610109174A CN105704919B CN 105704919 B CN105704919 B CN 105704919B CN 201610109174 A CN201610109174 A CN 201610109174A CN 105704919 B CN105704919 B CN 105704919B
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- copper
- layer board
- hole
- pcb
- layers
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Classifications
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K1/00—Printed circuits
- H05K1/02—Details
- H05K1/11—Printed elements for providing electric connections to or between printed circuits
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/40—Forming printed elements for providing electric connections to or between printed circuits
- H05K3/42—Plated through-holes or plated via connections
- H05K3/429—Plated through-holes specially for multilayer circuits, e.g. having connections to inner circuit layers
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
- H05K2203/07—Treatments involving liquids, e.g. plating, rinsing
- H05K2203/0779—Treatments involving liquids, e.g. plating, rinsing characterised by the specific liquids involved
- H05K2203/0786—Using an aqueous solution, e.g. for cleaning or during drilling of holes
- H05K2203/0789—Aqueous acid solution, e.g. for cleaning or etching
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- Engineering & Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Manufacturing & Machinery (AREA)
- Production Of Multi-Layered Print Wiring Board (AREA)
- Electroplating Methods And Accessories (AREA)
- Printing Elements For Providing Electric Connections Between Printed Circuits (AREA)
Abstract
The present invention relates to board production technical field, the production method of edge PTH hole and PCB on specially a kind of PCB.The present invention in edge PTH hole by being arranged the first layers of copper and the second layers of copper, and nickel coating is set between two layers of copper, the speed of growth of Yin Xi/nickel interface IMC at high temperature is significantly lower than tin/copper interface IMC speed of growth, nickel can be used as the barrier layer between tin and copper, so as to slow down and reduce the generation of IMC, the weldability of edge PTH hole is ensured.When production has the PCB of edge PTH hole of the present invention, by the pre-treating technology for controlling graphic plating, the nickel coating in edge PTH hole can be prevented to be oxidized, be passivated in the process of cleaning, so that ensureing can be adhering closely on nickel coating by the second layers of copper that graphic plating is formed.
Description
Technical field
The present invention relates to can slow down and reduce tin copper interface to close in board production technical field more particularly to a kind of PCB
The edge PTH hole of the total compound of gold, and the production method of the PCB with this edge PTH hole.
Background technique
PCB (Printed Circuit Board), Chinese is printed circuit board, also known as printed wiring board.On PCB
The route of different interlayers need to be connected to by plated-through hole (edge PTH hole).In subsequent use, also need through Reflow Soldering in part
It is total to generate interface alloy since the temperature of reflow soldering is up to 288-300 DEG C, between tin and copper for soldered elements in edge PTH hole
(Inter-metallic Compoud, IMC refer between scolding tin and soldering bottom metal compound, and under the conditions of heat is enough, tin is former
It son and be combined with each other, penetrate into, migrate and spread by weldering metallic atom, form one layer of chemical combination similar to tin alloy therebetween
Object), and the IMC between copper and tin mainly has benign Cu6Sn5With pernicious Cu3Sn, Cu6Sn5For white spheroidal structure, tin contains
Amount is 60%, and surface can be high, is generated at once when high-temperature molten tin, which is stained with, is soldered to clean copper face；Cu3Sn is grey column crystallization, tin
Content is 40%, and surface can only have Cu6Sn5Half, weldering thickness is gradually formed through high temperature or long-term ageing, will cause contracting tin or
Non-Dewetting.Wherein, Cu3Sn will affect solderability, especially repeatedly occur (in the manufacturing process of such as PCB, having under conditions of high temperature
May need to do over again because of other quality problems, also occur possibility of doing over again at the end PCBA), Cu can be accelerated3The generation of Sn, causes copper
Quickly stung erosion.And because edge PTH hole in hole wall layers of copper usually will not very thick (generally 25-35 μm), in multiple high temp
In the case of easily there is the situation of hole wall copper layer thickness deficiency, to influence the function of product.
Summary of the invention
Aiming at the problem that PTH on existing PCB is easy to generate IMC, providing can slow down and reduce on a kind of PCB the present invention
The edge PTH hole that IMC is generated, and the production method of the PCB with this edge PTH hole.
To achieve the above object, the present invention uses following technical scheme.
A kind of edge PTH hole on PCB, including hole body are covered with the first layers of copper, first layers of copper on the hole wall of the hole body
On be covered with nickel coating, the second layers of copper is covered on the nickel coating.
Preferably, first layers of copper with a thickness of 10-15 μm.
Preferably, the nickel coating with a thickness of 5-10 μm.
The production method of PCB with edge PTH hole described above, comprising the following steps:
S1 drilling: it is drilled on multilayer boards according to the prior art, makes to form hole body on multilayer boards；The multi-layer board passes through
Core material and outer copper foil are press-fitted together as one composition by prepreg.
The heavy copper of S2 and electric plating of whole board: heavy copper is carried out to multi-layer board and electric plating of whole board is handled, makes the hole body metal on multi-layer board
Change, the copper coating on the hole wall of hole body is known as the first layers of copper.
S3 nickel coating: by positive blade technolgy by the pattern transfer to multi-layer board on the additional film, nickel plating figure is formed；Institute
The figure on the additional film is stated only to open a window in position corresponding with hole body on multi-layer board；Then Nickel Plating Treatment is carried out to multi-layer board,
Make to form one layer of nickel coating on the hole wall of hole body.
Preferably, after carrying out Nickel Plating Treatment to multi-layer board, abrasive belt grinding processing is carried out to multi-layer board.
S4 outer-layer circuit: first taking off the film on multi-layer board, then by positive blade technolgy by the figure on the outer-layer circuit film
It is transferred on multi-layer board, forms outer-layer circuit figure；Then it is handled by graphic plating, forms outer-layer circuit on multilayer boards；
The copper coating formed on the hole wall of hole body when graphic plating is known as the second layers of copper.
Preferably, it is handled before first being done to multi-layer board before graphic plating processing, the pre-treatment is successively molten with citric acid
Liquid, water and sulfuric acid solution clean multi-layer board.
More there is choosing, the mass percent concentration of the citric acid solution is 3-6%, and solution temperature is 32 ± 2 DEG C, multilayer
Plate, which is placed in citric acid solution, cleans 5-7min.
Described when washing with water multi-layer board, water temperature is room temperature, scavenging period 6-10min.
The mass percent concentration of the sulfuric acid solution is 1-2%, and solution temperature is 20 ± 2 DEG C, and multi-layer board is placed in sulfuric acid
1-3min is cleaned in solution.
Process after S5: successively carrying out solder mask production, surface treatment and forming processes according to the prior art on multilayer boards,
PCB finished product is made.
Compared with prior art, the beneficial effects of the present invention are: the present invention in edge PTH hole by being arranged the first layers of copper and
Two layers of copper, and nickel coating is set between two layers of copper, the speed of growth of Yin Xi/nickel interface IMC at high temperature significantly lower than tin/
The speed of growth of copper interface IMC, nickel can be used as the barrier layer between tin and copper, so as to slow down and reduce the generation of IMC, ensure
The weldability of edge PTH hole.When production has the PCB of edge PTH hole of the present invention, by controlling the pre-treating technology of graphic plating,
The nickel coating in edge PTH hole can be prevented to be oxidized, be passivated in the process of cleaning, to ensure the second layers of copper formed by graphic plating
It can be adhering closely on nickel coating.
Specific embodiment
In order to more fully understand technology contents of the invention, combined with specific embodiments below to technical solution of the present invention
It is described further and illustrates.
Embodiment 1
The present embodiment provides the edge PTH holes on a kind of PCB, and the production method of the PCB with the edge PTH hole.Prepared
The specifications parameter of PCB is specific as follows:
Specific making step is as follows:
(1) multi-layer board
According to the prior art, internal layer circuit → pressing successively is made by sawing sheet → negative film technique, substrate is fabricated to not
The multi-layer board of drilling, i.e., the plate being press-fitted together as one to form by core material, prepreg and outer copper foil.It is specific as follows:
A, core plate, core thickness 1.1mm H/H sawing sheet: are outputed by jigsaw size 520mm × 620mm.
B, internal layer circuit (negative film technique): being produced, 8 μm of film thickness monitoring with vertical application machine, using Full-automatic exposure machine, with
5-6 lattice exposure guide rule (21 lattice exposure guide rule) completes internal layer circuit exposure, and line pattern is etched after development, and the measurement of internal layer line width is
3mil.Then the defects of opening short circuit, route notch, route pin hole of internal layer is checked, it is defective to scrap processing, flawless product
Downstream is arrived out.
C, it presses: selecting lamination appropriate to be pressed according to plate Tg after lamination, with a thickness of 2.5mm after pressing.
(2) it drills
According to the prior art, is drilled on multilayer boards using borehole data, make to form hole body on multilayer boards.
(3) heavy copper and electric plating of whole board
Heavy copper and electric plating of whole board processing are carried out to multi-layer board, so that the hole body on multi-layer board is metallized, on the hole wall of hole body
Copper coating is known as the first layers of copper.It is specific as follows:
A, the heavy copper of outer layer: hole metallization, backlight test 10 grades.
B, electric plating of whole board: with the current density electric plating of whole board 60min of 1.1ASD, 10 μm of hole copper thickness Min.
(4) nickel coating
By positive blade technolgy by the pattern transfer to multi-layer board on the additional film, nickel plating figure is formed；The additional phenanthrene
Figure on woods only opens a window in position corresponding with hole body on multi-layer board；Then Nickel Plating Treatment is carried out to multi-layer board, makes hole body
One layer of nickel coating is formed on hole wall.Then, abrasive belt grinding processing is carried out to multi-layer board.It is specific as follows:
A, nickel plating figure: positive blade technolgy makes nickel plating figure on multilayer boards, and nickel plating figure opens a window at edge PTH hole, and opens
The unilateral big 0.1mm more unilateral than edge PTH hole of window, i.e. other positions except edge PTH hole are all covered with dry film.
B, nickel plating: plating one layer of nickel in all edge PTH holes, current density 1.5ASD, electroplating time 30min,
Nickel coating with a thickness of Min7 μm.
C, abrasive belt grinding: grinding multi-layer board with abrasive band, to remove nickel extra in edge PTH hole and carry out at roughness to nickel face
Reason.
(5) outer-layer circuit
The film (nickel plating figure) on multi-layer board is first taken off, is then successively cleaned with citric acid solution, water and sulfuric acid solution more
Laminate；Then outer-layer circuit figure is formed in the pattern transfer to multi-layer board on the outer-layer circuit film by positive blade technolgy；Again
Then by graphic plating and outer layer etching process, outer-layer circuit is formed on multilayer boards；In the hole wall of hole body when graphic plating
The copper coating of upper formation is known as the second layers of copper.It is specific as follows:
A, multi-layer board: being placed in 32 ± 2 DEG C of citric acid solution first and clean 5-7min by pre-treatment, citric acid solution
Mass percent concentration is 3-6%；Then multi-layer board is sequentially placed into two pond bodies and cleans 3-5min with the water of room temperature respectively；
Then multi-layer board is placed in 20 ± 2 DEG C of sulfuric acid solution and cleans 1-3min, the mass percent concentration of sulfuric acid solution is 1-
2%.
B, outer-layer circuit figure: using Full-automatic exposure machine, completes outer-layer circuit with 5-7 lattice exposure guide rule (21 lattice exposure guide rule)
Exposure.
C, graphic plating: copper facing is tin plating, and copper facing parameter presses electroplating parameter: 1.8ASD × 60min.It is tin plating by 1.2ASD ×
10min, 3-5 μm of tin thickness.
D, outer layer etches: moving back film, etches, move back tin, route is fully etched out.
E, outer layer AOI: check whether internal layer has out the defects of short circuit, route notch, route pin hole, defective multi-layer board
Processing is scrapped, flawless multi-layer board enters downstream.
(6) process afterwards
According to the prior art, solder mask production, surface treatment and forming processes etc. are successively carried out on multilayer boards, are made
PCB finished product.It is specific as follows:
A, consent before welding resistance: the aperture that ink plug to aperture is 0.25mm by the aperture for being 0.30mm by aperture on aluminium flake
In, and press special jack Ink parameters baking sheet.
B, silk-screen welding resistance, character: using the white face wire mark brush TOP solder mask, and the face TOP character adds " UL label ".
C, it prints blue glue: stamping the blue glue of one layer of 0.7-1.2mm in golden finger position, protect golden finger position, be heating and curing simultaneously
Blue glue.
D, lead-free tin spray: one layer of uniform tin thickness is sprayed, is controlled with a thickness of 1-20 μm；Then blue glue is torn.
E, external form: gong external form, the +/- 0.05mm of external form tolerance.
F, electrical testing: the electric property of test-based examination production board.
G, final inspection: check whether production board has aesthetic appearance bad.
H, FQA: appearance, measured hole copper thickness, thickness of dielectric layers, green oil thickness, internal layer copper thickness etc. are taken a sample test again.
I, it packs: packaging being sealed to PCB by customer requirement, and is allowed to dry drying prescription and humidity card within a package.
Embodiment 2
The present embodiment provides the edge PTH holes on a kind of PCB, and the production method of the PCB with the edge PTH hole.
The structure of the edge PTH hole of the specifications parameter of the structure of the edge PTH hole of the present embodiment and the PCB that need to be prepared and embodiment 1 and
The specifications parameter of PCB is consistent, and the preparation method of PCB is also essentially identical with the preparation method of example 1, the difference is that production is outer
Pre-treating technology when sandwich circuit, specifically: multi-layer board being placed in first in 20 ± 2 DEG C of sulfuric acid solution and clean 1-3min, sulphur
The mass percent concentration of acid solution is 1-2%；Then multi-layer board is sequentially placed into two pond bodies clear with the water of room temperature respectively
Wash 3-5min；Then multi-layer board is placed in 20 ± 2 DEG C of sulfuric acid solution again and cleans 1-3min, the mass percent of sulfuric acid solution
Concentration is 1-2%.
For multi-layer board after above-mentioned pre-treatment, there is the phenomenon that being oxidized, being passivated in the nickel coating in edge PTH hole, after being unfavorable for
The copper coating formed when continuous graphic plating is adhering closely on nickel coating.
Embodiment 3
The present embodiment provides the edge PTH holes on a kind of PCB, and the production method of the PCB with the edge PTH hole.
The structure of the edge PTH hole of the specifications parameter of the structure of the edge PTH hole of the present embodiment and the PCB that need to be prepared and embodiment 1 and
The specifications parameter of PCB is consistent, and the preparation method of PCB is also essentially identical with the preparation method of example 1, the difference is that production is outer
Pre-treating technology when sandwich circuit, specifically: multi-layer board is placed in first in 32 ± 2 DEG C of citric acid solution and cleans 5-7min,
The mass percent concentration of citric acid solution is 7-9%；Then multi-layer board is sequentially placed into two pond bodies respectively with room temperature
Water cleans 3-5min；Then multi-layer board is placed in 20 ± 2 DEG C of sulfuric acid solution again and cleans 1-3min, the quality hundred of sulfuric acid solution
Dividing specific concentration is 3-4%.
For multi-layer board after above-mentioned pre-treatment, there is the phenomenon that being oxidized, being passivated in the nickel coating in edge PTH hole, after being unfavorable for
The copper coating formed when continuous graphic plating is adhering closely on nickel coating.
It is described above that technology contents of the invention are only further illustrated with embodiment, in order to which reader is easier to understand,
But embodiments of the present invention are not represented and are only limitted to this, any technology done according to the present invention extends or recreation, is sent out by this
Bright protection.
Claims (4)
1. the edge PTH hole on a kind of PCB, including hole body, the first layers of copper is covered on the hole wall of the hole body, which is characterized in that institute
It states and is covered with nickel coating in the first layers of copper, the second layers of copper is covered on the nickel coating；First layers of copper with a thickness of 10-15
μm。
2. the edge PTH hole on a kind of PCB according to claim 1, which is characterized in that the nickel coating with a thickness of 5-10 μm.
3. a kind of production method of PCB, there is edge PTH hole as described in claim 1, which is characterized in that described on the PCB
The production method of PCB the following steps are included:
S1 drilling: it is drilled on multilayer boards according to the prior art, makes to form hole body on multilayer boards；The multi-layer board is solid by half
Change piece and core material and outer copper foil are press-fitted together as one composition；
The heavy copper of S2 and electric plating of whole board: heavy copper is carried out to multi-layer board and electric plating of whole board is handled, so that the hole body on multi-layer board is metallized, hole
Copper coating on the hole wall of body is known as the first layers of copper, first layers of copper with a thickness of 10-15 μm；
S3 nickel coating: by positive blade technolgy by the pattern transfer to multi-layer board on the additional film, nickel plating figure is formed；It is described attached
The figure on the film is added only to open a window in position corresponding with hole body on multi-layer board；Then Nickel Plating Treatment is carried out to multi-layer board, makes hole
One layer of nickel coating is formed on the hole wall of body；
S4 outer-layer circuit: first taking off the film on multi-layer board, then by positive blade technolgy by the pattern transfer on the outer-layer circuit film
Onto multi-layer board, outer-layer circuit figure is formed；Then it is handled by graphic plating, forms outer-layer circuit on multilayer boards；Figure
The copper coating formed on the hole wall of hole body when plating is known as the second layers of copper；
It is handled before first being done to multi-layer board before graphic plating processing, the pre-treatment is successively to use citric acid solution, water and sulfuric acid
Solution cleans multi-layer board；The mass percent concentration of the citric acid solution is 3-6%, and solution temperature is 32 ± 2 DEG C, multi-layer board
It is placed in citric acid solution and cleans 5-7min；The mass percent concentration of the sulfuric acid solution be 1-2%, solution temperature be 20 ±
2 DEG C, multi-layer board, which is placed in sulfuric acid solution, cleans 1-3min；Described when washing with water multi-layer board, water temperature is room temperature, and scavenging period is
6-10min；
Process after S5: solder mask production, surface treatment and forming processes are successively carried out according to the prior art on multilayer boards, are made
PCB finished product.
4. a kind of production method of PCB according to claim 3, which is characterized in that in step S3, carry out nickel plating to multi-layer board
After processing, abrasive belt grinding processing is carried out to multi-layer board.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610109174.0A CN105704919B (en) | 2016-02-25 | 2016-02-25 | A kind of production method of edge PTH hole and PCB on PCB |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610109174.0A CN105704919B (en) | 2016-02-25 | 2016-02-25 | A kind of production method of edge PTH hole and PCB on PCB |
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| Publication Number | Publication Date |
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| CN105704919A CN105704919A (en) | 2016-06-22 |
| CN105704919B true CN105704919B (en) | 2018-12-07 |
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| CN201610109174.0A Active CN105704919B (en) | 2016-02-25 | 2016-02-25 | A kind of production method of edge PTH hole and PCB on PCB |
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Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109462942A (en) * | 2018-12-20 | 2019-03-12 | 东莞市鼎新电路有限公司 | A kind of processing method of pcb board edges of boards PTH half bore |
| CN113068327A (en) * | 2021-02-26 | 2021-07-02 | 胜宏科技（惠州）股份有限公司 | Method for manufacturing circuit board with uniformly plated holes |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101951735A (en) * | 2010-09-17 | 2011-01-19 | 深圳市集锦线路板科技有限公司 | Coppering and porefilling process for circuit board |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02206564A (en) * | 1989-02-04 | 1990-08-16 | Mitsumi Electric Co Ltd | Formation of through hole electrode on thermal head |
| JP4606018B2 (en) * | 2003-09-25 | 2011-01-05 | 富士機工電子株式会社 | Method for manufacturing printed wiring board |
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2016
- 2016-02-25 CN CN201610109174.0A patent/CN105704919B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101951735A (en) * | 2010-09-17 | 2011-01-19 | 深圳市集锦线路板科技有限公司 | Coppering and porefilling process for circuit board |
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